Missing feature in WHERE predicate builder in JcCypher

[DonCziken]

Use case is: fetch nodes by labels they are assigned with i.e. fetch all nodes which are of type BarrierArea OR BarrierInstance OR BarrierElement.

So based on above I'd like to build following cypher query using jCypher DSL:

MATCH (m) 
WHERE m:BarrierArea OR m:BarrierInstance OR m:BarrierElement 
RETURN m

However it seems that jCypher WHERE predicate builder is missing such an option. I had noticed that it is possbile to do following: WHERE.valueOf(n[0]).IN_list('BarrierArea', 'BarrierInstance', 'BarrierElement')

but this ends up to be much slower as it translates to following query, which does not scan by label, but do filtring:

PROFILE MATCH(n) where any(x IN labels(n) where x in ['BarrierArea', 'BarrierInstance', 'BarrierElement']) return n

I must say that I had found a workaround for this, which is following:

MATCH.node(n[0]).label("m:BarrierArea")
...
UNION.distinct()
MATCH.node(n[0]).label("m:BarrierInstance")
...
UNION.distinct()
MATCH.node(n[0]).label("m:BarrierElement")

but I'd much prefare to do it simple way (as first example), as workaround approach has some other disadventages for me.

So please let me know if that is possible (as maybe I missed something) and if not I would consider adding it :).

[Wolfgang-Schuetzelhofer]

Hi Krzysztof,

the solution is:

JcNode m = new JcNode("m"); clauses = new IClause[]{ MATCH.node(m), WHERE.has(m.label("BarrierArea")).OR().has(m.label("BarrierInstance")).OR().has(m.label("BarrierElement")), RETURN.value(m) };

This leads to the following cypher query:

MATCH (m) WHERE m:BarrierArea OR m:BarrierInstance OR m:BarrierElement RETURN m

Best regards, Wolfgang

On Tue, Aug 21, 2018 at 4:21 PM Krzysztof Gasior notifications@github.com wrote:

Use case is: fetch nodes by labels they are assigned with i.e. fetch all nodes which are of type BarrierArea OR BarrierInstance OR BarrierElement.

So based on above I'd like to build following cypher query using jCypher DSL:

MATCH (m) WHERE m:BarrierArea OR m:BarrierInstance OR m:BarrierElement RETURN m

However it seems that jCypher WHERE predicate builder is missing such an option. I had noticed that it is possbile to do founionunionunionllowing: WHERE.valueOf(n[0]).IN_list('BarrierArea', 'BarrierInstance', 'BarrierElement')

but this ends up to be much slower as it translates to following query, which does not scan by label, but do filtring:

PROFILE MATCH(n) where any(x IN labels(n) where x in ['BarrierArea', 'BarrierInstance', 'BarrierElement']) return n

I must say that I had found a workaround for this, which is following:

MATCH.node(n[0]).label("m:BarrierArea") ... UNION.distinct() MATCH.node(n[0]).label("m:BarrierInstance") ... UNION.distinct() MATCH.node(n[0]).label("m:BarrierElement")

but I'd much prefare to do it simple way (as first example), as workaround approach has some other disadventages for me.

So please let me know if that is possible (as maybe I missed something) and if not I would consider adding it :).

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[DonCziken]

Perfect! Thank you very much!